Air-brake



(No Model.) 3 Sheets-Sheet 1.

G. S. LEE. 5

AIR BRAKE;

vN0. 557,513. Patented Mar. 31, 1896.

ANDREW B.GRAHAM. PHDTO-UTNQWASHIN 6TB". Iii Cv (No Model.) 3Sheets-Sheet 2.

G. S. LEE. AIR BRAKE. No. 557,513. Patnted Mar. 31, 1896.

ANDREW EGRAHAM PHOTOYUTHQWASHINGTONDC.

(No Model.)

IIIIIIIWIIIIIIIIII G. s. LEE,

3 Sheefis-Sheet 3.:

AIR BRAKE.

Patentd Mar. 31, 1896.

ANDREW BGRMIAM,PHGTO'UTNQWASKINGTONIO Cf UNITED STATES PATENT FFIcE.

GEORGE S. LEE, OF I-IA\VTI-IORNE, NEW JERSEY, ASSIGNOR, BY MESNEASSIGNMENTS, TO THE NATIONAL AIR-BRAKE COMPANY, OF NElV YORK, N. Y., ACORPORATION OF NElV JERSEY.

Al R-BRAKE.

SPECIFICATION forming part of Letters Patent N0. 557,513, dated March31, 1896.

Application filed December 23,1895. SerialNo. 573,016. (No model.)

To aZZ whom it may concern.-

Be it known that I, GEORGE S. LEE, a citizen of the United States,residing at Hawthorne, in the county of Passaic and State of New Jersey,have invented certain new and useful Improvements in Air-Brakes; and Ido hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

My invention has relation to airbrakes which are especially designed andadapted for use on cable and'electric railways, and has for its objectthe provision of certain improvements in the air compressor or pump andin the mechanism by which the pump-piston is operated from one of theaxles of the car.

The devices forming the subject of the present application are includedin another application filed by me of even date herewith, in which theentire brake system is described and illustrated.

My present invention consists in the novel construction and combinationof parts hereinafterdescribed and claimed, having special reference tothe compressor and its operating mechanism.

In the accompanying drawings, Figure 1 is an end view, partly insection, of the compressor-pump. Fig. 2 is a plan view, partly insection, of the same. Fig. 3 is a central horizontal sectional view ofpart of the piston. Fig. 4: is a vertical central sectional view of thepump without the cylinder-heads. Fig. 5 is a side view of the pump. Fig.6 is an under side plan view of the pump, pump-operating mechanism, andautomatic governor mounted on a motor-car. Fig. '7 is a centralhorizontal section of the automatic governor. Fig. 8 is a plan View ofpump-operating gearing for radial cars.

The air compressor or pump comprises a pump cylinder or casing, areciprocating piston, and a rotary piston-shaft on which is mounted aneccentric and an eccentric-yoke to impart from the rotary shaft to thepiston the required reciprocating motion, the piston shaft being rotatedfrom one of the axles of the car through the medium of the gearing andconnected mechanism hereinafter described.

The casing or cylinder of the compressor consists of two substantiallysimilar flanged and interiorly-turned castings I 1 secured together bybolts ii through flanges I and having half-boxes I I at right angles tothe aXis of the cylinder to form bearings for the piston-shaft I, whichturns in suitable brasses 1 fitted in the boxes I I and extends outthrough one of the boxes to connect with the driving mechanism.

The pump or compressor casing is connected by an air-supply pipe withthe air-reservoir, from which another pipe C leads to the cylindricalchamber A A of the automatic governor, which is mounted in a casingsurrounding the pump-d rivin g mechanism. This chamber is adapted toreceive the pistons A A, the rod A A of which extends out through thehead of the chamber A. of the cylinder is provided with an air-inletport, to which is connected the air-conducting pipe O leading from theair-reservoir.

The compressor-piston, which constitutes one of the main features of myinvention, consists of two cylindrical disks or heads 1 1 havingprojecting from their inner faces the bored bosses 1W through which passthe bolts 1' 2, connecting the two heads together and leaving a spacebetween their inner faces for the play of the eccentric andeccentric-yoke by which the piston is reciprocated. The bosses i areformed with matching rabbets or offset shoulders i The inner faces ofthe heads I I are channeled or grooved at i to afford guidance to theeccentric-yoke 1' the latter being a rectangular collar made in twohalf-sections bolted together and bored out centrally to afford abearing for the eccentric I, which is keyed or turned solidly upon thepiston-shaft. A shim of steel is fitted in each groove 1' to afiord aslide bearing for the yoke and to take up all wear, being cheaplyreplaced when desired. As the piston-shaft rotates the eccentric impartsto the yoke a four-motion action, which alternately thrusts the pistonpositively in opposite directions. The cylinder and piston The otherhead of the pump are so constructed that the stroke of the piston willbe very short; but the latter is of much greater area than usual, itsdiameter being greater than the length of the pump-cylinder. At eachstroke therefore a large supply of free air is taken in, and in this waythe pump has an extra large compressing capacity under a slow motion ofthe piston. This is obviously a great advantage, as the strain, wear,and tear are reduced to a minimum and heating of journals avoided.

The pump is made with as few parts as possible, for the purpose ofobtaining strength and durability, and is made short, so as to economizespace under the car. The cylinder-heads are provided with suitablesuction and discharge valves, which need not be specifically described.

The piston of the compression-pump is operated from one of the axles ofthe car, which is designated A in the drawings, and I shall now describethe mechanism through which the piston is so operated and in connectiontherewith the construction and operation of the automatic governor,which, it may be generally stated, is to automatically disconnect thepump from the pump-operating mechanism when thepressure in the reservoirreaches its desired maximum and to reconnect the pump-piston and itsoperating mechanism at any desired minimum pressure.

Pump-operating mechanism.To the axle A of a four radial car a toothedpinion N is keyed, and such pinion engages with a large toothed wheel N,mounted loosely on a shaft N having its bearings in a suspensionframe N&c., which is securely bolted at one end to the boxes n mounted on theaxle on either side of the pinion N. Upon the shaft N is mounted a slideclutch member 0, which is held in rotative connection with the shaft N\Vhen the clutch member 0 is in pressure contact with the wheel N, thelatter communicates motion to the spindle N through the clutch, and thespindle in turn communicates motion to the rotary'shaft of thepump-piston through the universal shaft connection P P, the. Thisarrangement is shown in Fig. 8. hen the car is a fourwheeled car, anadditional idle gear-wheel is used, as shown in Fig. 6.

Any suitable form of flexible shaft connection may be employed, but Iprefer using what is known as the Mannesman flexible coupling. (Shownand described in Letters Patent No. 545,085, dated August 27, 1895.)

Now, 1t will be understood that while the car is running and the gearingis in active operative connection with the pump-piston the latter iscontinually compressing air and storing the same under increasingpressure in the reservoir. \Vhen, however, the desired maximum pressureis attained, the automatic governor operates, as hereinafter described,admitting the air under full pressure to the automatic governor, whichthen actuatcs the lever N and through the latter disengages the clutchmember 0 from the wheel N and allows the gears N N to rotateindependently of their connections with the pump-piston, which latterbecomes inactive. The lever N" is connected to suitablemanually-operative mechanism, so that in the event of a failure of theautomatic governor to work and upon the observance by the motorman of anab normal increase of pressure the clutch member 0 may be mechanicallywithdrawn and in this way the operation of the pump arrested.

The manner and means of supporting th suspension-frame and itsconnections at their forward end will depend in a large measure upon thestructure of the car. VVhen the brake is attached to a radial car, Iattach to the bottom of the car above the cylinder a segmental rail andsupport the suspensionframe upon this rail by means of a wheeled hanger,which will allow the car-body to turn and move laterally withoutdisturbing the position of the suspension-frame relative to the otherconnected parts.

The gears or other pumpdriving mechanism are inclosed within a suitablecasing 10, which is supported at one end upon the axle of the car bysuitable bearings, while the other end is suspended from the floor ofthe car or supported upon the channel-bearings 11 in such a manner as toyield and adapt itself to the forward and backward play of the axlecarrying the motor.

Automatic g0 vernor. A A designate hollow cylindrical members securedtogether by a screw-coupling and constitutinga cylinder larger at oneend than the other, the larger section A having its end closed by a headA provided with a stuffing-box A, through which passes a piston-rodcarrying two pistons A and A the former fitting and working in thelarger part A of the cylinder, while the latter fits and works in thesmaller part A. The piston-rod is formed in two sections A A attachedtogether by a screw coupling, and the piston A is formed integral withthe section A while the piston A is integral with the section A.Suitable packing a a is applied to the respective pis tons, which movesimultaneously as an integral structure. A lever N is pivotallyconnected to the end of the piston-rod A and is also connected to and byits movement serves to connect and disconnect the clutch, which isinterposed between the axle of the car and the pump. Upon the end of thecylinder is secured a valvechamber 13 having two valve-seats b b andvalves 11 6 formed on a stem b the valves seating oppositely to oneanother, so that as one is closed the other is opened. The stem Z)"extends beyond the valve b and is soeketed to receive the end of afollower I), which is carried by a compression-spring b, contained in acasing b the other end of spring I) bearing on a flanged IIO ITS

screw-plug b", which screws through the head 12 of the casing 6 and bymeans of which the tension of the spring Z) is regulated.

A pipe 0 leads from the valve-chamber to a compressed-air reservoir, anda branch pipe 0 leads from the pipe 0 to a chamber 0 containing pressureregulating valves arranged on the side of the section A of the cylinder.This chamber 0 is cylindrical in cross-section and contains threepiston-valves C O 0 mounted on a sectional stem 0, and the stem andvalves are pressed toward the end of the chamber into which the pipe 0enters by a compression-spring 0 that bears against the valve 0 and atthe other end bears against a flanged screw-plug C that screws throughthe head 0 of the chamber and serves as a means for adjusting thetension of the spring. A by-pass pipe D is connected with the chamber 0above and below the valve C and a valve D is arranged in said bypasspipe, being pressed against its seat (Z by a compression-spring d, andthe stem c1 of the valve projects into the chamber above the valve 0 abeveled surface d on the end of the stem contacting with a beveledsurface 0 on the valve 0 and serving to close the valve D when the valveC is moved by the pressure of air in pipe 0 Operation: WVhen by therotation of the car-axle and consequent operation of the pump thepressure in the air-reservoir has reached a maximum of, say, fifty-onepounds, the valve 12 will be opened against the pressure of spring 72which has been regulated by means of the screw-plug If, to exert aclosing pressure of fifty pounds on the valve 6 and the air will enterunder the piston A and will force up the piston-rod A A and operate thelever N to throw out of engagement the clutch that connects thedriving-axle and pump, thereby stopping the pump. Prior, however, tothis operation and after a pressure of thirtysix pounds has been gainedthe air will have entered the chamber 0 through pipe 0 and forcing upthe valves 0 G C will have closed the valve D in the by-pass pipe D andopened a port f leading from the cylinder A to the space in the chamber0 between the valves 0 and 0 from which space there is a free passage tothe open air through a port f. \Vhen the pump is stopped at fiftypoundspressure by the movement of pistonrod A A and pivoted lever N the pumpwill remain inactive until the air-pressure has been reducedsufficiently to allow the spring 0 which has been regulated to exert apressure of thirty-five pounds, to push down the stem 0 and open thevalve D of the by-pass pipe D and allow'air to enter the cylinder Aabove the piston A through a port f whereby the piston is depressed toits seat on the end of cylinder-section A and the pump is set in motionby the downward pull of the piston-rod A on the lever N.

The foregoing operations are repeated automatically from time to time asthe pressure in the air-reservoir reaches the maximum or minimum, andthus the proper and safe pressure requisite for efficient operation isconstantly preserved.

Having described my invention, I claim as new and desire to secure byLetters Patent 1. In air-brake systems, the combination with acompressor-pump and gearing for driving the same from the car-axle, of apiston-shaft connecting the pump-piston and gearing and made in sectionsconnected together by a universal coupling, substantially as described.

2. A compressor-pump for air-brakes, consistin g of a cylinder having abore of uniform diameter throughout its length, with air inlet andoutlet valves, a hollow cylindrical piston composed of two cylindricalrecessed heads, bolted together and formed with diametrical ways ontheir inner faces, a shaft passing laterally through said cylinder andpiston, and having an eccentric mounted or formed thereon, and arectangular sliding yoke embracing said eccentric and sliding in saidways, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

GEORGE S. LEE. Vitnesses THOMAS A. CONNOLLY, ANTHONY A. CoNNoLLY.

